1. Field of the Invention
In general, this invention relates to the field of magnetic hard disk drives, and more particularly, it relates to a substrate of a magnetic disk containing a hydrozone textured landing zone for contact with transducer heads and a method and apparatus for texturing a landing zone on the substrate of the magnetic disk.
2. Description of the Prior Art and Related Information
A great amount of development and effort in the field of magnetic hard disk drives has been directed to increasing the recording density of magnetic hard disk drives.
While a great number of factors are involved in achieving high recording density, one important characteristic is the need to maintain minimal tolerance between the transducer head and the recording surface, this tolerance being known as the "flying height."
In order to enable a low flying height, a very smooth planar surface is required on both the magnetic surface and the transducer head in order to provide an air "bearing" therebetween as the disk is rotated.
However, when the disks are not rotated, the transducer heads contact the recording surface and the precision planar surfaces of the disk and the head give rise to excessive stiction during start-up and stopping of the disk. This stiction during start-up and stopping of the disk causes wear between the transducer head and the recording surface which may eventually lead to malfunction of the disk drive.
To avoid, or significantly reduce, stiction between the transducer head and the disk, surfaces of magnetic disks heretofore have been intentionally roughened in selected areas to provide a landing zone for the transducer head.
Heretofore, in order to create a rough surface topography where the roughness allows lesser contact area between the transducer head and the disk, both mechanical abrasive techniques and laser techniques have been used.
In order to provide a mechanical abrasive texture in a contact start/stop (CSS) zone or landing zone on a substrate of a disk for the transducer head, the substrate may be rotated while a suitable grit, such as silicone carbide, is applied. The roughness so produced includes peaks which are jagged with sharp edges.
A disadvantage of mechanical texturing is the difficulty of accurate placement of the textured landing zone. Mechanically abrasive formed texture usually has transitions between the CSS zone and the recording data zone which arise from substrate or abrasive oscillation during texturing. These transition zones are undesirable in that they remove a substantial portion of a disk surface from being used as a recording area while at the same time do not provide useful start and stop operations for the transducer head.
As hereinabove noted, lasers have also been used for providing a surface topography for the CSS zone. A disadvantage of this method is when landing the head or slider, the head will intercept the rims thereby deforming them. Eventually, this deformation of the rims will increase the contact area between the head and the rims which increases stiction.